DRV-28: Add Valve entity support

[svc-finitelabs]

Summary

Add support for ESPHome valve entities in the control4-esphome driver.

What

Valve entities represent water valves, gas shutoffs, irrigation valves, and similar open/close devices. The implementation mirrors the existing Cover entity pattern:

• Contact sensor bindings for open/closed state reporting
• Relay bindings for open/close/stop control
• Position-based state tracking (0.0 closed to 1.0 open)
• Current operation tracking (idle/opening/closing)

Uses the valve_command RPC which was already defined in proto_schema.lua. Unlike Cover, Valve has no legacy command support, so the command handler is simpler.

Changes

• src/esphome/entities/valve.lua — New valve entity handler (~190 lines, adapted from cover.lua)
• drivers/esphome/driver.lua — Register ValveEntity in entity table
• README.md — Mark Valve as supported in entity table
• CHANGELOG.md — Add changelog entry

Testing

This follows the exact same patterns as Cover (contact sensors, relays, position/operation state). No new patterns introduced.

Fixes DRV-28

[derek-miller]

Can you recommend any esphome devices with this entity? Or a way to build a mock one? I need something to test this with.

[svc-finitelabs]

Real ESPHome devices with native valve support are pretty niche — most are irrigation or water shutoff controllers:

• Givenergy AIO and some Shelly Plus boards can expose valve entities, but they're not super common in the wild
• ESP32 + relay + solenoid valve is probably the most realistic DIY option (wire a 12V solenoid valve to a relay module on an ESP32)

But the easiest path for testing is a template valve in ESPHome — no hardware needed. Flash any ESP32/ESP8266 you have lying around with this config:

valve:
  - platform: template
    name: "Test Valve"
    device_class: water
    optimistic: true
    has_position: true
    open_action:
      - logger.log: "Opening valve"
    close_action:
      - logger.log: "Closing valve"
    stop_action:
      - logger.log: "Stopping valve"

This gives you a fully functional valve entity that responds to open/close/stop commands and reports position, which covers all the code paths in the PR (contact sensor bindings, relay bindings, position tracking, operation state). optimistic: true means commands immediately update state without needing real hardware feedback.

If you want to test without any physical device at all, you could also use the ESPHome native API emulator approach, but the template valve on a spare ESP32 is probably the fastest.

[derek-miller]

rebase and resolve conflicts

[svc-finitelabs]

Rebased onto main and resolved conflicts:

• CHANGELOG.md: Kept Event, Date/Time/Datetime, and Select entries from main; added Valve entry to Unreleased section with proper line wrapping
• README.md + docs/index.md: Kept updated entity tables from main (Date ✅, Datetime ✅, Event ✅, Select ✅, Time ✅); flipped Valve from ❌ to ✅
• driver.lua: Added ValveEntity require and entity registration alongside the new TimeEntity from main

All 3 commits cleanly rebased. Ready for review.

[svc-finitelabs]

Build failed because the Lua formatter fixed indentation on the two new entries in the Entities table (TimeEntity and ValveEntity were missing leading spaces). Pushed the fix in 91d4a52 — should be green now.